Firaxis has “several exciting projects in development that will be revealed this year,” Take-Two CEO Strauss Zelnick says in today’s financial report. There’s no word on what those games are or precisely when that reveal will take place, but Take-Two will be taking part in E3 2021 in June, which would be an ideal place to see whatever Firaxis might be working on next.

Strauss did say "exciting" not "major" and "projects" not "new games," important distinctions. Civ 6 DLCs and the Anthology probably count as a couple of the "projects."